<template>
   <el-menu default-active="1-4-1" background-color="#545c64" text-color="#fff" active-text-color="#ffd04b"
      class="el-menu-vertical-demo" @open="handleOpen" @close="handleClose" :collapse="isCollapse">
      <h3>{{ isCollapse ? '后台' : '通用后台管理系统' }}</h3>
      <el-menu-item @click="clickMenu(item)" v-for="item in noChildren" :index="item.path + ''" :key="item.path">
         <i :class="'el-icon-' + item.icon"></i>
         <span slot="title">{{ item.label }}</span>
      </el-menu-item>
      <el-submenu v-for="item in hasChildren" :index="item.path + ''" :key="item.path">
         <template slot="title">
            <i :class="'el-icon-' + item.icon"></i>
            <span slot="title">{{ item.label }}</span>
         </template>
         <el-menu-item-group v-for="(subItem, subIndex) in item.children" :key="subItem.path">
            <el-menu-item @click="clickMenu(subItem)" :index="subIndex + ''">{{ subItem.label }}</el-menu-item>
         </el-menu-item-group>
      </el-submenu>
   </el-menu>
</template>

<style lang="less" scoped>
.el-menu-vertical-demo:not(.el-menu--collapse) {
   width: 200px;
   min-height: 400px;
}

.el-menu {
   height: 100%;
   border: none;

   h3 {
      color: #fff;
      text-align: center;
      line-height: 48px;
   }
}
</style>

<script>
export default {
   data() {
      return { menu: [] }
   },
   methods: {
      handleOpen(key, keyPath) {
         console.log(key, keyPath)
      },
      handleClose(key, keyPath) {
         console.log(key, keyPath)
      },
      // 点击事件实现路由跳转
      clickMenu(item) {
         this.$router.push({
            name: item.name
         })
         this.$store.commit('selectMenu', item)
      }
   },
   computed: {
      // 判断菜单栏有无子菜单
      noChildren() {
         return this.asyncMenu.filter((item) => !item.children)
      },
      hasChildren() {
         return this.asyncMenu.filter((item) => item.children)
      },
      // 控制侧边栏的收缩
      isCollapse() {
         // console.log(this.$store);
         return this.$store.state.tab.isCollapse
      },
      asyncMenu() {
         return this.$store.state.tab.menu
      }
   }
}
</script>
